This invention relates generally to exercise equipment and deals more particularly with an attachment which converts an ordinary stationary exercise bicycle into an electronic exercise machine.
Conventional exercise bicycles employ mechanical arrangements of various types to vary the load or resistance which the rider must overcome to pedal the bicycle. Typically, pedaling of the bicycle rotates a fly wheel equipped with a mechanical braking mechanism that offers resistance to the fly wheel rotation. The most common type of brake includes a small wheel which is brought into contact with the fly wheel with varying amounts of pressure. The rider encounters increased resistance when the pressure is increased. Caliper type brakes are also used and include either felt or rubber brake pads for applying the braking force to the wheel. Another type of brake that has been employed in exercise bicycles includes a flat belt which is drawn around the wheel and can be tightened to apply the braking force. The progressive tightening of the belt applies increasing resistance to turning of the wheel.
In all of these mechanical brakes, friction is relied upon to provide the braking action, and the components are subjected to heat and wear resulting from the frictional forces. Another problem is that the measurement of the resistance is either not possible or is inaccurate at best. Consequently, the resistance is normally adjusted by "feel" which can vary considerably depending upon the personal mood of the rider and other factors. The result is that a well planned exercise program involving the systematic use of known loads cannot be carried out on the conventional exercise bicycle.
In recent years, specialized exercise bicycles which incorporate modern electronics have been developed. These electronic systems can apply virtually any desired load and can accurately control and monitor the resistance which must be overcome. In addition, the load can be varied in a programmed manner in order to simulate riding the bicycle up and down hills, for example. The speed, the work that is being done, the pulse rate, the elapsed time of the exercise routine, and other information can be accurately determined and displayed to the rider so that he can continuously monitor his progress through the exercise routine. The primary drawback with electronic exercise machines of this type is that they require a specialized bicycle which makes the cost of the machine excessive.